A copper-clad laminate includes a copper foil and a polyimide film superposed thereon. A wiring circuit board is produced by processing the copper foil of the copper-clad laminate into a given wiring pattern by etching.
Such a copper-clad laminate has been conventionally produced by directly applying an adhesive solution to a polyimide film, drying the adhesive solution by heating to form an adhesive layer, and subsequent laminating a copper foil to the polyimide film through the adhesive layer (see, for example, patent document 1).    Patent Document 1: JP-A-10-126035